Pile handing methods

ABSTRACT

A pile handling tool is supported at the upper end of a tubular guide, and includes a jacking mechanism for advancing a pile longitudinally relative to the guide, and a mast projecting upwardly above the jacking mechanism and carrying an aligning structure for laterally engaging a pile and holding it in properly aligned position with respect to the guide. The mast is desirably mounted for retracting movement from an upwardly projecting active position to a laterally retracted inactive position. The jacking mechanism may be constructed to rotate one of two successive pile sections relative to the other to complete a connection therebetween.

This is a division of application Ser. No. 710,450, filed Aug. 2, 1976,now U.S. Pat. No. 4,051,587.

BACKGROUND OF THE INVENTION

This invention relates to improved apparatus and methods for handlingpiles as they are moved into position for supporting a work platform orother structure, such as for example an off-shore drilling rig.

In erecting an off-shore drilling platform, it is customary to firstmove to the desired drilling location a framework or `jacket` whichincludes a number of generally vertical tubular pile guides and to thenadvance downwardly through each of the guides a series of pile sections,which are connected together longitudinally and are of a compositelength to reach and ultimately be driven into the floor of the ocean orother body of water, so that the platform and drilling equipment maythen be supported at an elevated location by the jacket.

As a pile section is moved into engagement with and then advancedthrough a guide of the discussed type, it is often very difficult tomanipulate the usually very large and heavy pile section in a mannercontrolling effectively its movement and orientation, and maintainingits proper alignment with the guide and with another section previouslypositioned in the guide as a connection is made between the twosections. These and other pile handling problems are in many instancesrendered more troublesome by wave induced movement of some or all of thepile manipulating equipment.

SUMMARY OF THE INVENTION

The present invention provides apparatus and methods which greatlyfacilitate the handling of a seris of pile sections as they areconnected together and progressively advanced downwardly through thelocating guide of a jacket structure. The invention enables twosuccessive sections to be held very effectively and positively inaccurately aligned relation as one section is moved downwardly intoengagement with and connected to a next lower section, and then as thetwo sections are advanced downwardly together in preparation forconnection to a third section.

A tool embodying the invention includes a support structure which isadapted to be located and supported at the upper end of a pile guide,and which carries a jacking mechanism through which a pile can extenddownwardly into the guide. This jacking mechanism is power operable toprogressively advance one or more sections of the pile downwardlyrelative to the guide, and desirably includes two gripping units, one ofwhich is movable vertically relative to the other to effect a jackingoperation. The two gripping units may include slips which are wedgedagainst the outer surface of a pile section to releasably grip it.Powered means may be provided for turning one of the gripping unitsrelative to the other in order to relatively rotate two successive pilesections to complete a joint therebetween.

In addition to the jacking mechanism, the support structure alsopreferably carries an aligning mast, which projects upwardly beyond thejacking mechanism and carries aligning means engageable with a pilesection to laterally support it in a properly aligned and preciselycontrollable orientation with respect to the jacking mechanism and thepile guide. A stabbing unit may be carried by the support struture, andcontain and form a downwardly tapering guide throat which is engageablewith the lower end of a pile section to center it as it moves downwardlyinto the jacking mechanism and guide.

The aligning mast is desirably mounted to the support structure forretracting movement between an active position in which it is properlylocated for aligning engagement with a pile section, and a laterallyretracted inactive position. This movement may be a swinging typemovement, in which the upwardly projecting mast swings laterallyoutwardly and downwardly about a hinge axis at essentially the lower endof the mast. The mast may be held in this retracted position duringmovement of an add-on pile section initial locating engagement with thetapering throat of the stabbing unit, and/or during ultimate powereddriving of the pile into the ocean floor.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and objects of the invention will be betterunderstood from the following detailed description of the typicalembodiment illustrated in the accompanying drawings in which:

FIGS. 1 to 6 show diagrammatically several successive steps which may beperformed in utilizing equipment embodying the invention, with thecat-walk omitted from some of the views for simplicity and clarity.

FIG. 7 is a greatly enlarged side view of a machine embodying theinvention, shown for simplicity of illustration and description in adirectly vertical position, rather than the slightly inclined positionof FIG. 3 in which the device is normally utilized;

FIG. 8 is an elevational view taken on line 8--8 of FIG. 7;

FIG. 9 is a plan view of the upper aligning apparatus taken on line 9--9of FIG. 8;

FIGS. 10 and 11 are horizontal sections taken on lines 10--10 and 11--11respectively of FIG. 8;

FIG. 10a is an enlarged detail view of a portion of FIG. 10;

FIG. 12 is a fragmentary vertical section taken on line 12--12 of FIG.10; and

FIG. 13 is a fragmentary vertical section taken on line 13--13 of FIG.8.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring first to FIG. 1, there is illustrated at 10 a `jacket` whichhas been positioned at an off-shore location in a body of water 11, andwhich consists of a framework typically having a number of spaced legs12 projecting downwardly to positions of support on the floor of thebody of water. The jacket also includes a number of tubular pile guides13 through which elongated piles are to be advanced downwardly toultimately be driven into the floor of the body of water for supportinga work platform at the upper ends of the piles above the water level.Each of the piles is normally formed of a number of pile sections whichare connected together in end-to-end relation, with an initial one ofthese sections, as represented at 14 in FIGS. 1 and 2, preferably beingpremounted and temporarily tack welded in each guide at the time ofmanufacture of the jacket and before its movement to the drillinglocation. The joints between successive pile sections are in someinstances formed by welding, and in other cases by interfittingmechanical connectors on the sections which may be joined rigidlytogether by predetermined relative rotary movement of the two sections,as for instance in a joint of the commonly used `breech block` type inwhich interrupted threads are brought into connected relation by limitedrelative rotary movement of the sections.

The pile sections are usually externally cylindrical, and may be formedas metal pipes. Each of the pile guides 13 preferably is of straightcylindrical configuration externally and internally about an axis 16 ofthe guide, and carries an annular tool support 15 extending about guide13 at a location spaced beneath its upper edge and welded or otherwiserigidly secured to the guide, with the support having an annularupwardly tapering frustoconical upper tool support surface 17 centeredabout axis 16. The internal diameter of the guide is just slightlygreater than the external diameter of the pile sections, to effectivelylocate the pile section relative to the guide. The guides 13 desirablyhave their axes 16 inclined at a small `batter` angle a with respect tothe true vertical, to direct the piles downwardly at a correspondingangle into the ocean floor.

A pile handling tool constructed in accordance with the presentinvention is illustrated generally at 18 in FIG. 1 and the otherfigures, and is adapted to be supported successively on the upper endsof the various pile guides 13, in a position such as that illustrated inFIGS. 2 and 3, for use in lowering the pile sections downwardly throughthe guides and to the ocean floor. If the axis of a particular guide isinclined, as discussed, the longitudinal axis 19 of tool 18 is similarlyinclined and aligned with the guide axis 16 when the tool is supportedon that guide. However, to simplify the illustration and description ofthe details of the tool 18, it has been illustrated in FIGS. 7 through13 in a directly vertically extending position, with the axis 19extending precisely vertically.

With reference now to FIGS. 7 and 8, the tool 18 includes a lower mainframe or support structure 20 which is formed of a number ofappropriately shaped parts welded or otherwise secured rigidly together,and which frame is adapted to rest on the upper tapering support surface17 of part 15 and be supported stationarily thereby. The frame 20carries a jacking mechanism 21 at a location above the pile guide, andat its upper end carries a stabbing bell 22 for receiving and centeringa lower end of a pile section. An aligning mast 23 projects upwardlyfrom frame 20, and is connected thereto for swinging movement about ahorizontal axis 24 between the positions of FIGS. 2 and 3. An aligningunit 124 for laterally engaging the pile is carried at the upper end ofmast 23. The main frame 20 has an annular flaring base element 25, withan undersurface adapted to engage and be supported by, and flaringfrustoconically and downwardly in correspondence with, the upper surface17 of part 15. Welded to and projecting upwardly from base element 25,the frame 20 may also include four tubular circularly spaced legs orcorner posts 26 whose upper ends are rigidly welded to and carry thestabbing bell 22. The structure 20 may be reinforced at a locationbeneath the jacking mechanism 21 by plates 28 extending between andwelded to corner posts 26, but with these plates and all other portionsof the frme structure being offset far enough from axis 19 of the toolto leave a clear passage entirely though the tool for extension of apile therethrough.

At one of its sides, frame 20 carries a work platform 29, having a floor30 on which a workman stands and which extends at an angle with respectto axis 19, so that in the inclined FIG. 3 position of use the toolfloor 30 is horizontal. The work platform may include rails 31 extendingabout three sides of the platform, with the platform being appropriatelysecured rigidly to the rest of the frame structure by means typicallyincluding angular braces 32 at the underside of the platform. A controlpanel 33 is secured to one of the legs 26 of the frame and carries anumber of hydraulic control valves 34 positioned for manual actuation bya workman standing on floor 30 to control the delivery of pressurizedhydraulic fluid from a power source 134 to the various hydraulicactuating mechanisms later to be described.

The jacking mechanism 21 includes two vertically spaced upper and lowergripping units 35 and 36, the lower of which is positioned at a fixedlevel on the frame 20, while the upper gripping unit 35 is actuableupwardly and downwardly parallel to axis 19 relative to frame 20 andlower gripping unit 36, between the full line and broken line positionsof FIG. 7, preferably by four hydraulic piston and cylinder mechanisms37.

The upper gripping unit 35 of the jacking mechanism (see FIGS. 10, 12and 13) includes a rigid horizontal base plate 38 having arcuatelycurving recesses 39 in its periphery for partially receiving the fourcorner posts 26 of frame 20. A number of arcuate guide bushings 139 arecarried in at least some of the recesses 39 for slidably engaging thecorresponding corner posts in a relation locating and guiding plate 38for upward and downward movement relative to the frame. The upper endsof the piston rods 39 of piston and cylinder mechanisms 37 are connectedrigidly to base plate 38 to cause upward and downward movement of thebase plate in correspondence with the delivery of pressurized hydraulicfluid to opposite ends of the cylinders 41 of mechanisms 37. The axes 42of the four circularly spaced piston and cylinder mechanisms 37 areparallel to and spaced circularly about axis 19 of the tool, insymmetrical relation with respect thereto. The cylinders 41 are securedrigidly to frame 20 in any appropriate manner as for instance by bolts43 securing flanges on the cylinders to walls 28 of the frame.

At its upper side, the rigid horizontal base plate 38 of gripping unit35 rigidly carries an annular upwardly projecting ring 44 (FIGS. 10 and13), to which outwardly projecting horizontal walls 45 are welded forproviding the mentioned connections 40 between the upper ends of thepiston rods 39 and the base plate. More particularly, each of thesewalls 45 may contain an opening 140 through which an upper reduceddiameter portion of the piston rod projects for threaded connection to aretaining nut 40, with the piston rod having a larger diameter beneathwall 45 and at a location of extension through an opening 46' in theperipheral portion of base plate 38.

At the upper side of base plate 38 and within annular ring 44, there ismovably mounted an annular slip bowl assembly 46 including a horizontalbottom ring 47 and an upstanding ring 48 having an inner downwardlytapering frustoconical wedge surface 49 centered about axis 19. A seriesof circularly spaced slips 50, having gripping elements 51 at theirradially inner sides of a type capable of transmitting both vertical androtary forces to or from an engaged pile, have downwardly and inwardlyinclined outer wedge surfaces 52 engageable with surface 49 to cam theslips radially inwardly in response to downward movement relative to theslip bowl assembly. The slips are guided for such movement and in allpositions retained against surface 49 by guide elements 53 (FIGS. 10aand 13) which are secured rigidly to upper portions of surface 49 byscrews or the like and have lateral flanges 54 spaced from and parallelto surface 49 to define therewith guideways receiving opposite sideflanges 55 of the individual slips and retain them for controlledsliding movement.

The slips are actuable upwardly and downwardly by an annular ring 56(FIG. 13), which has portions 57 projecting into recesses in the sidesof the slips, with pins 58 carried by the slips being received withinhorizontal slots 59 in portions 57 to allow radially inward and outwardmovement of the slips as they are actuated upwardly and downwardly. Ring56 is moved upwardly and downwardly by a series of similar circularlyspaced vertical piston and cylinder mechanism 60, whose cylinders may besecured rigidly to the outer side of ring 48 of the slip bowl structure,and whose pistons may have their upper ends rigidly connected by nuts 61to ring 56. As will be apparent, the axes 62 of these piston andcylinder mechanisms extend vertically and parallel to main axis 19 ofthe machine. Bottom ring 47 of the slip bowl structure is securedrigidly to upstanding ring 48 by bolts or otherwise, and has anundersurface 63 engageable in bearing relation with the upper surface ofbase plate 38 to allow rotary movement of the slip bowl structure andslips about axis 19, with this structure being centered by ring 44secured to base plate 38. The slips and associated parts are turnedabout axis 19 by two horizontal piston and cylinder mechanisms 64 (FIG.10), whose cylinders are pivoted at 65 to brackets 66 appropriatelysecured to ring 44, with openings in that ring being provided at 67 topass the piston and cylinder mechanisms therethrough. The piston rods ofmechanisms 64 are pivotally connected at 68 to hinge elements 69 weldedto the outer side of slip bowl ring 48.

A number of circularly spaced vertically elongated members 70 may bewelded to the inner downwardly tapering surface 49 of slip bowl ring 48at locations between different groups of the slips 50, with upperportions of members 70 being received within recesses 71 in slipactuating ring 56. The radially inner surfaces 72 of members 70 mayextend directly axially, that is, parallel to axis 19, and be spaced acommon distance therefrom, which distance is greater than the radialdistance of the clamping elements 51 of the slips from axis 19 in thelower pile gripping positions of the slips, but less than the distanceof elements 51 from axis 19 in the upper retracted positions of theslips. Consequently, in the retracted positions of the slips, members 70can engage and guide and locate a pile section and prevent unnecessarywearing contact with the slips.

The lower gripping assembly may be basically the same as upper assembly35, except that the slip bowl assembly 46a, including the rigidlyconnected bottom ring 47a and upper tapered ring 48a (corresponding toparts 47 and 48 of the upper assembly) are not free for either verticalor turning movement, but rather are rigidly secured to frame 20. Forthis purpose, the bottom horizontal ring 47a may typically be supportedon and be rigidly welded or bolted to a horizontal plate 147a which isin turn secured rigidly to plates 28 carried by legs 26 of the frame.Coacting with slip bowl assembly 46a, there are provided a series ofcircularly spaced slips 50a actuable upwardly and downwardly relative tothe slip bowl by circularly spaced vertical piston and cylindermechanisms 60a through an actuating ring 56a, with the slip bowlcarrying spaced vertical members 70a, all corresponding to andfunctioning in the same manner as the similarly numbered parts 50, 56,60 and 70 respectively.

The stabbing bell 22 is essentially annular about axis 19, andfrustoconical in shape to provide within its interior a downwardlytapering pile centering throat, with the diameter at the upper end ofthis throat being substantially greater than the external diameter ofthe piles to be handled, and with the diameter of the lower end of thethroat being just slightly greater than that pile diameter. Thus, a pilemay be easily stabbed into the throat within the bell 22, and thencentered by the bell as the pile is lowered therethrough.

Mast 23 may take the form of an open framework as shown, whose lowerportion is received essentially about the upper end of main frame 20,with the various members forming the mast typically including tworelatively long rear corner members 73, two shorter forward cornermembers 74, and various cross pieces and brace members 75 extendingbetween and rigidly interconnecting members 73 and 74. A ladder 76 maybe secured to a rear side of this mast structure, and a second and lowerladder 77 may be secured to the front side of the frame 20. At its lowerend, near the lower extremities of the two members 73, the mast has twohorizontally aligned tubular hinge or bearing portions 78, which areengageable with and received about two aligned hinge pins 79 secured toopposite sides of frame 20, to mount the mast for the previouslymentioned swinging movement between the full line and broken linepositions of FIG. 7. The mast is power actuable between these positionsby two piston and cylinder mechanisms 80, the cylinders of which arepivotally secured at 81 to opposite sides of frame 20, and the pistonsof which are pivotally connected to the mast at locations 82, which areat the lower ends of the two members 74 respectively.

The aligning unit 124 at the upper end of mast 23 includes a rigidstructure 83 which has the essentially U-shaped horizontal sectionillustrated in FIG. 9, and which may be fabricated from a number ofrigid metal plates appropriately welded or otherwise secured together toform the desired structure and reinforce it to take the forces exertedthereagainst by a pile section in use. The U-shaped structure 83contains and defines a recess 84 extending into the structure from oneof its sides (the left side in FIG. 7), with this recess being of awidth w just slightly more than the external diameter of the pilesection, to receive the pile in confined and located relation. A pair ofrollers 85 mounted to structure 83 for rotation about horizontal axes 86and 87 are positioned to engage the pipe at circularly spaced locationsand effectively locate it when the pipe is resting against the rollers.In the inclined FIG. 3 position of the apparatus, the inclination of thetool and pile are such that the weight of the pile is exerted directlylaterally against rollers 85. The edges of the recess 84 within whichthe pile is received in structure 83 may be defined by verticallyextending walls 88 which are welded to and follow the inner edges of theother plates forming structure 83 and therefore present pile engagingareas of substantial size.

The U-shaped structure 83 is mounted for limited transverse shiftingmovement relative to mast 23, along the axis 89 of FIG. 9, and for thispurpose may carry aligned bearing rings 90 depending from opposite sidesof structure 83 and received about two externally cylindrical hinge pins91 rigidly secured to the upper end of the mast at its opposite sides. Ahorizontal piston and cylinder mechanism 92 has its cylinder secured tothe mast and its piston connected at 93 to structure 83, to move thatstructure laterally along axis 89 and thereby very precisely locate thisaligning structure relative to the jack mechanism and other portions ofthe apparatus.

To now describe the preferred method of use of the discussed pilealigning machine, assume first of all that the jacket 10 of FIG. 1 hasbeen positioned at a desired off-shore location, with each pile guide 13containing an initial pile section temporarily welded thereto, and witha number of additional pile sections being carried by the barge 94 ofFIG. 1 to a location adjacent the jacket. As illustrated in FIG. 1, thetool 18 is lifted by crane 95 to a position above one of the pile guides13, and is gradually lowered by the crane about the pile section 14 andguide 13 to a position of support on part 15 (as in FIG. 3). The mast ofthe tool is normally elevated during such movement of the tool onto theguide, and the tool is turned about the guide axis 16 until the mast isat the side of the tool which corresponds to the lateral direction inwhich axis 16 is inclined. In this position, the tool is so located withrespect to the tilt of the guide that an inclined pile can be held bygravity against rollers 85.

After the tool has been positioned in this manner, the aligning mast 23is power actuated by piston and cylinder mechanisms 80 from itsupstanding position to its laterally retracted position of FIG. 2, sothat the crane can lower a next successive pile section to the FIG. 2position just above stabbing bell 22, without interference being offeredby the mast. With the upper gripping unit 35 in its uppermost position,above the upper end of initial pile section 14, a second pile section14' is gradually lowered into contact with the tapering throat withinthe stabbing bell, so that the bell can center the pile and direct itdownwardly into alignment with and close proximity to the upper end ofthe first pile section. The mast is then swung upwardly to its FIG. 3position in which it engages and accurately aligns the second pilesection at an upper location, with that section being lowered until itis received within and is then gripped by upper gripping unit 35. Theupper gripping unit and top aligning unit 124 will thus hold the topsection in precise alignment with the lower section for completion of arigid connection therebetween, as by welding, or by bringing togetherthe connector elements of an interrupted thread type `breech block`connection, or any other type mechanical joint. Controlled adjustment ofthe precise setting of the mast in a left to right direction as viewedin FIG. 3 assures exact alignment of the pile sections in one direction,while movement of top aligning structure 83 relative to the mast bypiston and cylinder mechanism 92 accurately aligns the sections in aplane offset 90° from the plane of adjustment of the mast itself.

When the sections have been properly aligned, the upper grippingassembly 35 is operated to gradually lower the upper pile section 14'into contact with the upper end of the lower pile section 14, and thetwo section may then be welded rigidly together or otherwiseinterconnected. If an interrupted thread connection is provided, thepiston and cylinder mechanisms 64 of the upper gripping unit may behydraulically operated to turn the slips of that gripping unit aboutaxis 19 in order to apply rotative torque to the upper pile section tocomplete the connection between the two sections.

After this connection has been completed, the temporary weld betweensection 14 and guide 13 is broken, and the two joined pile section arelowered together along axis 19 to a position such as that shown in FIG.4 in which the upper end of the second pile section 14' is near thestabbing bell 22. In some instances this lowering can be effected by thejacking mechanism, but in FIG. 4 it is assumed that section 14' islowered by the crane, with the suspension line from the crane carryingan elevator 195 releasably clamped to the upper end of the pile, andwith mast 23 retracted laterally as shown in FIG. 4 to avoidinterference with the elevator.

After the second pile section 14' has reached the position of FIG. 4,the upper gripping unit 35 in its uppermost position is actuated intogripping engagement with section 14', and the pick-up elevator 195 isreleased or returned to the barge to get a next successive pile section.The gripping unit 35 is moved downwardly relative to the bottom grippingunit 36, to correspondingly move the interconnected pile sectionsdownwardly, following which lower gripping unit 36 is clamped againstthe section 14' and the upper unit 35 is released to return upwardly fora next successive lowering operation. This jacking action is continueduntil the upper end of section 14' reaches the position of FIG. 5 justabove lower gripping unit 36, in which position a third pile 14" can beconnected to section 14'. The third section 14" is of course located andaligned by the same procedure discussed in connection with section 14',being first stabbed into the upper locating bell 23 with the mastretracted, and then aligned by the mast and lowered to the FIG. 5position, in which the upper gripping unit 35 can grip section 14" andmove it downwardly for connection to section 14'. In FIG. 5, it isassumed that this connection is a `breech block` type joint in whichsection 14' has an upper connector portion 193 with external interruptedthreads adapted to engage corresponding internal interrupted threadswithin section 14". The connection is thus completed by actuating uppergripping assembly 35 to first lower section 14" into engagement withsection 14' and then turn section 14" relative to section 14' to bringtheir threads into rigidly interconnected relation. After the joint hasbeen completed, the connected sections are lowered until the thirdsection 14" is positioned for connection to a next successive pilesection, and the cycle is repeated until enough sections have beenconnected together to reach the ocean floor.

As has been mentioned, the first add-on pile section is in most caseslowered to the FIG. 4 position by the pick-up elevator 195 suspendedfrom the crane. This is because of the provision of external groutingribs on the first add-on pile section which should not be gripped byunits 35 and 36. All subsequent pile sections, however, such as section14", are preferably lowered by the jacking mechanism itself, aftercompletion of the connection at the lower end of each section to thepreceding section. That is, after the section 14" in FIG. 5 has beenconnected to section 14', the three interconnected sections are thenlowered by the jacking mechanism, by first gripping section 14" in uppergripping unit 35 in its uppermost position, then moving that upper unitand the pile downwardly relative to the lower released gripping unit 36,following which the lower unit is gripped against the pile and the upperunit 35 is released and returned upwardly, to again grip the pile andlower it through another step, etc.

When the pile reaches a length at which it becomes necessary to commencedriving the pile into the ocean floor, a drive section 97 is connectedto the uppermost pile section, being joined thereto at 98 (FIG. 6), anda conventional pile hammer 99 is placed about this drive section andenergized to exert downward driving force thereagainst to force the pileinto the ocean floor. During this driving operation, the mast isretracted laterally as shown in FIG. 6, to be out of the way of the piledriver 99. When the hammer leads reach the level of stabbing bell 22,drive section 97 is detached from the uppermost pile section, as bybreaking a threaded connection therewith, and another pile section canthen be connected to the upper end of the string, with drive section 97at the upper end thereof, to enable further driving of the stringdownwardly into the earth formation beneath the body of water.

After the required number of pile sections have been installed anddriven into place, the tool 18 is again connected to the line from thecrane and lifted thereby off of the guide through which the pilesections have been installed, and the tool may then be moved to aposition of support by a second of the pile guides 13 for use inlowering a series of pile sections downwardly therethrough in the samemanner discussed in connection with the first guide. In this way, pilescan be progressively applied to all of the guides, and the entire jacketcan be secured in position relative to the ocean floor, with a workingplatform ultimately being mounted on the secured jacket.

While a certain specific embodiment of the present invention has beendisclosed as typical, the invention is of course not limited to thisparticular form, but rather is applicable broadly to all such variationsas fall within the scope of the appended claims.

I claim:
 1. The method of driving a pile into an offshore seabed thatcomprises:supporting on a pile guide the weight of a pile handling toolwhich includes a jacking mechanism and pile aligning means above thejacking mechanism; aligning a pile section with said jacking mechanismby said aligning means; jacking said pile section longitudinallydownwardly relative to and within said pile guide by operation of thejacking mechanism while said tool is supported by the guide; moving saidaligning means laterally from an active position to a retractedposition; moving a second pile section to a position above the firstsection while said aligning means are in said retracted position;returning said aligning means to said active position; aligning saidsecond section with said first section by said aligning means,connecting said sections together, moving said aligning means toretracted position again; moving said aligning means to retractedposition again; and driving said connected pile sections downwardlywithin said jacking mechanism and guide and into the seabed by forceexerted against an upper portion of said second section while saidaligning means are in said retracted position.
 2. A pile handling methodutilizing a tool having a jacking mechanism, pile centering means at theupper end of said jacking mechanism, and a retractable mast carryingaligning means which are spaced above said jacking mechanism in apredetermined upwardly projecting active position of the mast, saidmethod comprising:moving the lower portion of a pile section intoengagement with said centering means in a relation locating said lowerportion for entry into said jacking mechanism; maintaining said mast,during said movement of the pile section into engagement with thecentering means, in a retracted inactive position lower than said activeposition to avoid damaging contact of the pile section with the mast;then raising said mast relative to said jacking mechanism and centeringmeans from said inactive position to said upwardly projecting activeposition; locating an upper portion of said pile section by engagementwith said mast-carried aligning means at a location above the jackingmechanism; and moving the pile section by said jacking mechanism.
 3. Themethod as recited in claim 2, including supporting the weight of saidtool on a pile guide with said jacking mechanism and centering meansaligned with said guide.
 4. The method as recited in claim 2, in whichsaid movement of the pile section by the jacking mechanism includeslowering of the pile section longitudinally downwardly by the jackingmechanism.
 5. The method as recited in claim 2, in which said movementof the pile section by the jacking mechanism includes lowering of thepile section longitudinally downwardly by the jacking mechanism, saidmethod including then lowering said mast again to said inactiveposition, moving a second pile section into locating engagement withsaid centering means, raising said mast to said active position,locating an upper portion of said second pile section by said aligningmeans, connecting said second section to the first in end to endrelation, and then jacking the two connected pile sections downwardlylongitudinally by said jacking mechanism.
 6. The method as recited inclaim 2, in which said movement of the pile section by said jackingmechanism includes turning said pile section relative to another pilesection therebeneath by said jacking mechanism and thereby completing aconnection between the two sections; and then advancing the twoconnected pile sections downwardly together.
 7. The method as recited inclaim 2, including connecting said pile section to another pile sectiontherebeneath.
 8. The method as recited in claim 2, including drivingsaid pile section downwardly within said jacking mechanism by forceexerted against an upper portion of the section above said jackingmechanism.
 9. The method as recited in claim 2, in which said movementof the pile section by the jacking mechanism includes jacking saidsection downwardly relative to another aligned pile sectiontherebeneath, said method including then connecting said sectionstogether.
 10. The method as recited in claim 2, in which said movementof the pile section by the jacking mechanism includes jacking saidsection downwardly relative to another aligned pile sectiontherebeneath, and then turning one of said sections relative to theother to complete a connection therebetween.
 11. The method as recitedin claim 2, including lowering said mast again to said inactiveposition, and driving said pile section downwardly by force exertedagainst an upper portion of the section while said mast is in saidinactive position.
 12. A pile handling method utilizing a tool havingpile centering means, and a retractable mast carrying aligning meanswhich are spaced above said centering means in a predetermined upwardlyprojecting active position of the mast, said method comprising:movingthe lower portion of a pile section into locating engagement with saidcentering means. maintaining said mast, during said movement of the pilesection into engagement with the centering means, in a retractedinactive position lower than said active position to avoid damagingcontact of the pile section with the mast; then raising said mast fromsaid inactive position to said upwardly projecting active position; andlocating an upper portion of said pile section by engagement with saidmast-carried aligning means at a location above said centering means.13. The method of handling a pile section utilizing a tool having ajacking mechanism and an aligning mast projecting upwardly thereabove,that comprises:aligning said pile section with said jacking mechanism bysaid mast while the mast is in a predetermined active position; movingsaid mast to a retracted position; and subsequently driving siad pilesection downwardly relative to the jacking mechanism by force exerteddownwardly against said section at a location above the jackingmechanism and while said mast is in said retracted position.
 14. Themethod of handling a pile section utilizing a tool having a jackingmechanism and an aligning mast porjecting upwardly thereabove, thatcomprises:locating said pile section relative to said jacking mechanismby said mast while the latter is in a predetermined active position;advancing said pile section longitudinally downwardly by said jackingmechanism; moving said mast to a laterally retracted position; andmoving a second pile section to a position above the first while saidmast is in said retracted position.
 15. The method as recited in claim14, including returning said mast to active position, aligning saidsecond section by said mast, and connecting said sections together.